Epimediums could be the answer . . . lovely evergreens, grown mainly for their foliage (greens, bronzes etc.), with tiny flowers in summer. Spreads slowly, is low-growing and perfectly happy in dry shade. (I'll be uploading some pics later.)
Or Pachysandra?

Euphorbia amygdaloides, vinca or ivy should all be OK there. If you went for an epimedium as Sheila suggests you'd need to get a variety that keeps its leaves in winter. I have one that's great while it's flowering, but loses its leaves in autumn and is invisible for half the year.
Have you tried Hart's tongue fern (Asplenium scolopendrium)? I had them growing out of walls under trees - they are really tough. I've just read that they like limey soils - I'm here to tell you that they're not fussed if you have acid soil to offer instead. :-)

I'd recommend Hedera helix varieties, or second, Hypericum calycinum

Didn't know that, Beattie . . . all my Epimediums keep their leaves! Vinca is a good suggestion.

My disappearing Epimedium is Epimedium youngianum 'niveum' which is quite small and has white flowers. I have E. sulphureum (I think that's what it is..) as well and its bronze leaves are quite attractive in winter.

Geranium Nodosum makes effective and pretty ground cover in dry shady spots. My epimedium is warleyense, the reddish and yellow one, very pretty and great for ground cover.